package com.company;

import java.util.Scanner;

public class HJ26 {
    public static void main(String args[]){
        Scanner in = new Scanner(System.in);
        String line=in.nextLine();
        char[] arr=line.toCharArray();
        for(int i=1;i<arr.length;i++){
            if(!Character.isLetter(arr[i])){
                continue;
            }
            int j=i-1;
            char tmp=arr[i];
            while(j>=0 && Character.toLowerCase(arr[j])>Character.toLowerCase(tmp)){
                arr[j+1]=arr[j];
                j--;
            }
            arr[j+1]=tmp;
        }
        for(int i=0;i<arr.length;i++){
            System.out.print(arr[i]);
        }
    }
}
